380879 ZnO Supported Ultrathin Au Nanowires for Photoelectrocatalytic Applications

Tuesday, November 18, 2014: 4:45 PM
International 4 (Marriott Marquis Atlanta)
Annamalai Leelavathi1, Giridhar Madras1 and N Ravishankar2, (1)CeNSE, Indian Institute of Science, Bangalore, India, (2)MRC, Indian Institute of Science, Bangalore, India

Fuel cells are believed to be promising technology to challenge the increasing energy demand particularly direct alcohol oxidation reaction displays high energy density. This work presents the synthesis of hybrid ZnO/ultrathin Au nanowires1 and their support and geometry-dependent electrocatalytic performances towards alcohol oxidation upon illumination. Geometry control of Au nanostructures is a useful method to modify its electrocatalytic properties– by tuning electrochemical active surface area, exposed facets and aspect ratio.2 Grown ultrathin Au nanowires exhibited outstanding electrochemical activity that is much higher than that exhibited by Au nanoparticles. ZnO support provides an excellent stability for Au nanowires during reaction and also produced reactive charge carriers under excitation, thus assisting in oxidation current generation. Since both ZnO and Au nanowires exhibited ethanol oxidation reaction independently via photoirradiation and applied potential, respectively, the direct coupling of Au nanowires and ZnO, hybrid displayed impressive photoassisted electrocatalytic performance and excellent stability.3The mechanism of the synergetic effect of ZnO supported Au nanowires towards photoelectrocatalytic activity is proposed based on electrochemical measurements. We envision that the as-synthesized semiconductor-ultrathin nanowires hybrids hold great possibility for integration as catalyst in future fuel cell technology.

References

1.    Halder, A.; Ravishankar, N., Ultrafine Single‐Crystalline Gold Nanowire Arrays by Oriented Attachment. Advanced Materials 2007,19(14), 1854-1858.

2.    Porter, N. S.; Wu, H.; Quan, Z.; Fang, J., Shape-control and electrocatalytic activity-enhancement of Pt-based bimetallic nanocrystals. Accounts of chemical research 2013,46(8), 1867-1877.

3.    Drew, K.; Girishkumar, G.; Vinodgopal, K.; Kamat, P. V., Boosting fuel cell performance with a semiconductor photocatalyst: TiO2/Pt-Ru hybrid catalyst for methanol oxidation. The Journal of Physical Chemistry B 2005,109 (24), 11851-11857.


Extended Abstract: File Not Uploaded